Patent GB-662727-A (GB)
Title: Improvements in or relating to balance-winding systems for colliery and like shafts
IPC: B66B17/12
Filed: 1949-10-27
Abstract: 662,727. Lifts; balancing. KERRIDGE, F. B. Sept. 26, 1950. [Oct. 27, 1949] No. 27621/49. Classes 78 (ii) and 78 (iii). In a water counterbalanced mine cage winding system of the kind in which a pair of cages connected by a cable passing over a pulley each carry a tank which is automatically filled with water at the pit head and emptied at the bottom of the shaft, so that when a brake on the pulley is released, one cage descends and raises the other cage; a predetermined quantity of water is automatically supplied to the tank. The tank 30, Fig. 2, of the upper cage is loaded from one of a pair of service tanks 24 which are each supplied through a pipe 34 and have inlet valves 39, 35 and an outlet valve 42, the valve 35 having a manually adjustable float 36 to vary the quantity of water in tank 24. Assuming one tank 24 to have been charged, valves 35, 42 to be closed and valve 39 to be open; on the arrival of a cage, member 37 lifts an arm 49 and closes valve 39, and member 45 lifts counterbalanced arms 44 so opening valve 42 and allowing the charge to flow into the tank through a flexible spout 46, baffle plates 47 being provided to prevent surging. On release of the brake the cage descends, valve 42 automatically closes, valve 39 automatically opens and water flows into tank 24 until, on attainment of a predetermined charge, the valve 35 closes. The bottoms of the cages are joined by a heavy cable (not shown) which counterbalances the hoist rope, and furthermore, increases both the acceleration of the cages during the first half of the travel and the retardation during the latter half of the travel. The retardation is also decreased during the second half of the travel by jettisoning water from the down cage at predetermined points in its run, this is effected by one or more pipes 49, Fig. 4, which are of adjustable height and are normally closed by a valve 53, however, when an arm lead in line not shewn strikes an abutment located in the shaft the valve is lifted and, since counterweight 55 has passed over centre, remains open until it is re-closed later by another abutment at the pit head, thus the level of the water in the tank falls to the level of the top of pipe 49 and the jettisoned water flows through a pipe 50, a slotted pipe 51 and a pipe 57, and is collected either in the sump, or at an intermediate level, from which collection points it is pumped back to the main storage tank at the pithead. A valve 48 is automatically opened at the bottom of the travel to drain the tank. To assist in re-winding the cages should a fault develop in the system, a motor (not shown) may be coupled to the main supporting pulley (not shown). This pulley continuously drives a compressor supplying a hydraulic accumulator with fluid for the brake system. The necessary setting of float 36 is determined by a device which indicates the out of balance of the cages and comprises a pair of hydraulic piston-cylinder units and a differential pressure gauge which measures the torque applied to the brake shoes by the pulley when the cages are stationary. Alternatively, the piston-cylinder units may be secured to sliding pulleys which engage the winding rope on each side of the main pulley and force the rope out of its normal run.